Before we get you confused, this is a completely different game than what has been mentioned of The Dark Knight, that has been rumored (the only answer we got was, "We (EA) haven’t announced a superhero game.") between Pandemic and EA.

The new game, Batman: Arkham Asylum will be published by Eidos and developed by Rocksteady Studios. According to Game Informer’s August Edition, "This completely original title explores Gotham City’s darkest location, the infamous Arkham Asylum. But as a routine prison transfer goes wrong, the Joker sets his demented plan into action and Batman comes face to face with an army of his worst enemies. In a dark and gritty setting reminiscent of Bioshock (with a story co-written by Paul Dini), Arkham Asylum is setting the stage for a true-to-character Batman game." The edition will be out August 18th, with two different cover.

Batman: Arkham Asylum will be on the PC, X 360 and PS3 , the release date at this point is 2009. According to the article, the story is written by Paul Dini (Batman: The Animated Series, Detective Comics). The story is not tied into any movie or show, and will be on the darker side of the Dark Knight. The story will start out with Joker surrendering himself and subsequently taking over Arkham because of some secret the facility holds. 

We tried to do a bit of further investigating and ran into something interesting. Rocksteady Studios site has the Batman Insignia on it, and some sort of countdown, but we still can’t seem to figure out what its for. If you can figure it out email me wade [at] gamersdailynews.com, and your right, Ill send you something.

Edit: We’ve also learned that it may be on the Unreal Engine 3.0 and the licensing includes all 70 years of comic books, so this story could be wide open, or may have many, many addons

Edit: 08.13.2008 New Info Revealed and GDN has it